I've actually wondered myself from time to time... Maybe Bitmover is right, but i always wondered why other company's that accept bitcoin as a payment don't jump on the potential traffic from the biggest bitcoin community...
I mean, as long as you sell a product that's more or less mainstream and most (tech savvy) people will buy from time to time AND you accept BTC as a payment option, i just feel it would make sense to promote on bitcointalk.
I have also read from certain mixer-owners that the traffic they got from bitcointalk was much better quality wise than the traffic they got elsewhere....
I was in contact with both Ledger and Trezor a few years back regarding marketing on bitcointalk. Trezor said they'd consider it (but never looked into it further) while the ledger rep I was talking to asked what I could do with a $500/month marketing budget. lol