I've never tried any Kammock products. If you like them, that's what is important. Obviously, there are many who like the Kammock. Otherwise, they would go out of business.
There are several thousand members on this board, several hundred of which are fairly regular contributors. Among those, a few hundred try a lot of different gear just for the fun of trying it. A bunch more (like me) have tried several different things so we could find the set up we like best. I know many folks here look for new features and then chew the fat about pros and cons. Some manufacturers are participating members here, too. So there is a bias toward them (no pun intended).
I do know that HH marketed the water catch system, but without the bottle attachment feature. They also marketed the stability that weight at the corners provides as well as the fact you could drink the H2O.
It seems to me that Kammock either has not been abundantly agressive with their innovations or they have not marketed the members of this forum very hard.
The road to success is always under construction.