Great explination on some of the benefits these Bitcoin forks get from forking from the original as well as the marketing and branding value they get from it. they also create a fragmentation in the market with new investors who arent very clued up thinking well I cant afford one BTC but this other type of Bitcoin I can afford to have a whole one.
These sort of marketing tactics also encourage trading and push projects up in market cap when they really would not have that value had they been a non bitcoin branded coin