People coming in herds to support are either the "sanctity of marriage" people or the "they have a right to free speech" people, most commonly a combination of both. They may be coming in herds right now but eventually they will not, & ultimately Chick-Fil-A will have lost business from their more liberal & pro-gay rights customers, which is just a foolish move. Yes, Chick-Fil-A does have the right to an opinion & free speech, & they can say whatever they want - but from a business perspective, it is a foolish longterm move (obviously right now it's increasing business but it very much seems short term).
A fast food place serves chicken & french fries. A good comparison to make for this is a waiter. Let's say you're at a restaurant & your waiter starts telling you their personal beliefs, ones that happen to be... very strong opinions. Do they have that right? Yes, free speech is a right that should always be there. But does the customer WANT to know what their server thinks? Most likely, no, & it would annoy them. I'm just putting it in a practical context. What they're doing is unprofessional, & in the example of the waiter, the waiter would probably be fired. I mean, let's be real, would you want someone to tell you their views on a controversial issue like "family values" or birth control while serving you waffle fries? Talk about a quality eating experience... with a strong stance to boot.
Free speech is very important but it's not always used wisely, hence I don't understand this argument when it comes this scenario.