Yeah, I know, but even when I run some official material I tone it down a lot for my games.
"Carnival" type entertainer magicians is plausible, but assuming a magic-common world breaks things down a lot.
For example, I am a 1st-level caster with the light cantrip. Consider the simple torch, 1 cp, burns for 1 hour (same as the cantrip's duration). Instead of adventuring, I find some local taverns or inns and offer my services to go around their premises touching sconces with the light cantrip. If each establishment has 10 torches, that is 30 an hour, or assuming 8 hours 240 torches. Even at 25% off the cost of a torch, that is 180 cp or 1.8 gp per night. Maintaining a modest lifestyle is 1 gp per day, leaving me a profit of 8 sp per night or about 288 gp per year in net profit.
Why bother adventuring?
Now, if you want to play in a world were your lantern-lighters are going around casting light for hours on end, or have an old city where the taxes paid for continual flame hundreds or thousands of time to light the streets, that's fine but not what I would want to play in.
(I know you said you prefer the sort of low-magic game I described, the above point was "you" in general.)