Business owners operate (or should) within the law. Why would they roll over for a prez and ignore the First Amendment rights of citizens?

The 1st amendment is about Congress not making a law against free speech. 
A boss has every right to tell an employee what is an is not acceptable speech while at work and in some cases while off the clock. 
NFL has every right to require player to act a certain way while on in the stadium. 
I have requirements of my workers if they don't follow them, they will cease to be a worker.  

One of the attributes of free expression is that it can also be used against you. Some folks having liberties and trying to exercise them is much like an infant with a loaded pistol(Uh oh I just crossed over into the Second Amendment didn't I ?) They enjoy "rights" as long as it can be used as a weapon,(Oh Hell, there I go again). When one runs out of inane, mindless prattle, the last resort is name  calling and slurs(See above). Even the most sacred liberties have something of a downside, but then, ear plugs can be purchased cheaply. By the way, employers do in fact have input into your first amendment rights. That issue was settled decades ago. I spent forty years working for employers that could put the brakes on your "freedom of expression". They are still doing it.  

Not sure what this is all about - doesn't really make sense to me.  But - if all people did was only go around expressing themselves then nothing would get done.  Self-expression has its limits.  Most of us, unless we are very rich, need to make a living too.