You can find some bounties in Services section that is not limited to an ICO. Some were to promote the correct way of using English language, and to enhance your linguistic approach. Some were to promote Gambling sites, Mixing sites, a Cryptocurreny, and etc. But yes, in my own opinion, 70 percent of Bounties are made to be in ICO, especially now.
It's more than 90% made to be for ico as the number of bounties campaigns in
services board is incomparable to it in
bounties board (i countd 10 new ico announcments in one day here in the forum). Sharing risks with investors is the main factor for this bounty prosperity in the ICO system.
Bounties could be a useful tool for all sectors in the market; means it's not only in the bitcointalk forum. I didn't find so much thing by searching about similar programs in Marketing.