Well, when we say community, we refer to a large number of people or entities, who may be affiliated to many smaller or disparate sub-structures.Community almost always refers to a varied and large audience, yet with certain things, which maybe certain interests, opinions, or religion or ethnicity.
On the other hand, group is indeed most often used for a small number of people or other entities, each of which may or may not be large. Also, a group is not as natural a collection as community. A group maybe formed by some of us just now, but a community arises on its own and comes together, and has more naturally common attributes. Similarly, one can be expelled from a group, if he disrespects the rules, but one cannot be banned from a community per se, unless it is something very artificial like a virtual social networking aggregate that is moderated etc.
E.g. we talk about the international community of researchers of a certain field, say Physics, or the international community of institutional investors (each of which is an institution like a bank and consists of millions of people), whereas we say G8- a group of nations.
Judging from your description, I might say...
People participating in the same activity
People involved in the same thing I am doing
People around me/nearby while I am ____________
Otherwise, I would just stick to the exact descriptions you used, if possible: "the people driving on the same road," "people in the same building as me," etc. Sometimes the best way to solve a grammatical question is to say exactly what you mean rather than trying to be general.
I think we tend to use "relevant" about information, not people. I don't say "people relevant to my life"; I would say either "people involved in my life" or "people who affect my life."
Best Answer
'How is that still in vogue ' would do
In vogue refers to the fact that it is still in fashion or the majority take a liking in doing something in a particular vogue.
Example- Traditional dresses like sarees are still -'in vogue' in india.