Unless this is a different situation, the Miller employee fired for drinking Bud Light was not at a Brewers game.
http://www.kmbc.com/r/4191531/detail.html
The article says Miller has no corporate policy in this area, but leaves it up to the distributors to set the policy.
I'm sounding like a hard-ass in my opinion. But nothing in U.S. law says an employer can't set a policy about employees using competitors' products. It's not harrassment to get onto someone for it. In fact, calling it that cheapens the word.
There are probably exceptions, too. I'm sure quite a few Mac workers are encouraged to use MS products in order to figure out how they work, and vice versa. I'd guess plenty of bottles of Pepsi have been brought into Coke plants for some kind of analysis of the product. If you are employed building some high-end product, you probably aren't expected to own it.
Ford may not care
too much if line employees drive Toyotas or Hondas, but I doubt they'd tollerate an
executive who didn't own a Ford. Contract employees can also have condidtions in their contracts that prohibit the use of a competitor's product. In other words, your standing in the company probably matters a lot, too.
In general, Coca-Cola may just shrug if an employee uses the competitor's product once in a while on his own time. I'm sure Coke employees eat at Pizza Hut (Pepsi-owned), for example. Especially since Coke doesn't have an equivalent.
But at the same time, I think Coke would be quite upset if a uniformed employee parked his Coke truck in a Pizza Hut lot, and proceeded to go in for lunch.
A grocer may not care if a bagger occasionally shops at another store. However, I doubt the grocer would feel the same way if people tell him they see the store's produce manager regularly buying fruits and vegetables at a competitor.
