In some countries people only tend to climb on bolts, in some it's mixed (some area's are bolted others are clean) and in some trad is the only way to climb.
Climbing trad or bolts involves not just the issue of a 'pure' route, but also has a safety issue, an access issue, habits, quality and experience(s) of local climbers and much more.
So deciding to bolt or not is, I find, a hard decision.
To my opinion bolting routes should be avoided when it's possible to climb the route on trad gear. I even think it's even not necessary to bolt a route following modern techniques when the 'old' way of bolting is actually not really 'safe'. Climbing safety is something relative I think, and it's part of the beauty involved in the sports: it's your own personal decision to climb a route or not.
Some climbers are very active in this issue. And even chop away bolts.
In this movie a little example of a route that doesn't have to be bolted: The Doors, and 8b (French grading). Matteo Della Bordella climbs the route.