@maltese
Unfortunately there are no clear answers to your question and this has been debated on here numerous times. We literally go around in circles talking about what's safe.
If you want objective, clinical data, then you will be hard pressed to find anything of substance. You will mainly find anecdotal information based on life experiences; which is unreliable. Data is notoriously hard to analyse because of the webs/connections that are created. For example, you could correlate yellowing teeth as being a precursor to lung cancer. This however is not true and only tells a story on one of the most well known ways of acquiring lung cancer: smoking. As you can see - if smoking is not part of the equation - then you could easily draw conclusions that are incorrect. This occurs regularly in science which is why things have to be thoroughly studied.
The problem with anecdotal stories is similar. A lot of the time people don't actually receive a diagnosis (remember, tinnitus is a symptom). In many cases diagnoses' are based on the most likely cause; which is usually noise induced. Now imagine that a person has tinnitus due to an undiagnosed vascular problem, or maybe intracranial pressure. There are many others we could go with here. Now let's say this person believes they have noise induced tinnitus, and over the course of a few months attend a few shows which get a bit loud. However, they use earplugs and feel fine; the noise is reduced significantly. Then imagine the next day or later, their tinnitus spikes, and they go through a rough patch. The obvious and most immediate thoughts would be directed towards the shows they attended, because that's the most likely cause. But, in this instance we could say this person is wrong, and it is in fact a worsening of their vascular condition which is causing the spike. You can change my example of using a vascular problem for a multitude of other causes (prolonged stress, undiagnosed TMJ, allergies, high blood pressure, neck muscle problems, prescription meds, otosclerosis, eustachian tube problems, impacted earwax, etc etc).
Stories like these are often presented as facts, but in reality they are only anecdotal. You could represent this in many other ways. For example, someone may believe the prescription drugs they have been taking caused their tinnitus, since it only started whilst using them. A classic case of connecting the wrong dots (a common fault all humans possess known as a human bias). In this case they have noise induced tinnitus, but it has been cumulative. The noise that was the final straw which caused the T didn't register with the person at all. In fact, they may not even remember the noise or event that caused it, but the years of clubs and gigs is the contributing factor here; not the drugs they are taking. It's the coincidental factor that makes this so compelling, but ultimately completely untrue.
This is why stories online can only be taken with a pinch of salt. You must do your own research and follow what you believe. Talk to some experts and take their advice.
My own opinion is that you shouldn't wear earplugs when the noise is negligible. It's just not possible anyway unless you want to live in a padded cell. You will come across babies crying, dogs barking, trains and cars going by etc all the time. I'm my opinion - with the advice of the various experts I've talked to - non of this needs protection. Over protection can just lead to other problems including hyperacusis. Save your ear plugs for the theatres, concerts, parties, loud bars, power tools etc.
I also strongly believe that the 'worry' of your ears getting damaged, in everyday situations, is the real problem and not the noise. You can end up with phonophobia as
@Michael Leigh pointed out, or other psychological conditions which will only make your tinnitus and mental health worse. It's a form of obsession similar to OCD when it's taken too far, and it's unhealthy for your mind and central nervous system. You will end up becoming a very jumpy person.
Live your life as normally as possible, and try your best not to worry too much.