My present employer did offer stock as an incentive. It was a great program.
Past tense: FASB changed the rules, the discount changed, employee participation (naturally) dropped, it stopped being cost effective to offer this plan.
Being able to walk away from that company no strings attached mitigates that risk.
Being financially liable should the company go under is why co-owners share in the profits beyond salary/hourly wages.
There already is a way to share in the profits and success of your company--set up your 401(k) to include company stock. More generally, if your company does well and isn't run by shitheads, bonuses and raises happen. What exactly does it mean when one of Microsoft's 94,000 employees (http://www.microsoft.com/en-us/news/inside_ms.aspx#RevenueHe...) is a co-owner?