> Do these coffee machine vendors seek to use patents to protect their sales of coffee?

A couple years ago this was a debate in France, Nespresso lost but it was because of anti-competitive behavior[1]. There's apparently[2] plenty of 3rd party nespresso pods : around 50 brands worldwide.

[1] https://arstechnica.com/business/2014/04/nespresso-open-sour...

[2] http://www.beveragedaily.com/Processing-Packaging/Coffee-cap...