With all the implied hate against groupon, it's still a billion dollar company.
Almost any markrtplace start up can be cloned locally. But even more importantly, even before lyft and groupon existed there were small local shops executing on a similar idea. But it took Groupon to acheive scale.
What's next? You'll begin deriding McDonalds because all it is is a burger shop that anyone can start?
Scaling shit from $100,000 biz to 100mil revenue is hard as fuck. Exhibit A: all the groupon competitors that no longer exist.