As a decently sized guy (6'3 ~300), my BMR is around 2700.. so it wouldn't be that hard to add 300 calories worth of energy expenditure, at which point I'd be eating below maintenance level.

Would depend on your height and weight I think.

You are asking a person who clearly has spent a ton of time figuring out how to manage their weight if they've tried calorie tracking?

When you hear someone stating that they find burning 3,000 calories a day necessary it seems like a logical question. You can't burn that many calories without first adding them.

I assume this person has found that burning that many calories is easier for them than restricting their diet more.

Exactly. I eat pretty healthy, but I like food. Sure, I could starve myself and be miserable. But why do that when exercise solves the problem and it has all sorts of other positive side effects? So I can sit on my butt all day like the people from Wall-E? No thank you.

All of my serious (recreational) bike rider friends eat a lot more than 3000 calories/day prepping for their weekend bike rides.

Yes, some exercise routines require well over 2000 calories a day, but that's still pedantically missing the point of my comment.

If somebody is confused about why they need to burn 3000 calories a day to keep from gaining weight, they're eating too much.

Serious cardio will burn a LOT of calories. If a person who is NOT doing serious cardio needs to exercise to a 3000 cal deficit every day to maintain weight, they should lower their caloric intake.