I think the first thing to understand is to yourself. Meaning, ask yourself "why compete"? Seriously. If you're doing it for fun/enjoyment, then ask yourself "what makes it fun and enjoyable"?
For me and our team, the fun is the comradere <spelling> and the level of the competition (ala. as many highly competitive teams as possible). For this reason we only compete in sanctioned competitions with fairly high payouts because they attract a higher level (averages being averages) of competitor.
For you the answers could be completely different. Perhaps its the socialization and locale that only a local ribfest can provide.
We dont sell/vend barbecue even on those where we can, and I'm including MBN competitions where we're cooking about 200# of meat if we dont cook hog, and if we do we're at about 330# (meaning PLENTY of meat for vending). The reason is that we focus on the competition, but again that gets back to the question "why compete".
Only you can answer these for yourself.