Locs at work

So i know this topic has been discussed alot.. but it was just brought to my attention .. at my job orientation yesterday.. my question is if you keep locs clean and looking nice .. why is it to un acceptable in certain businesses....In certain hotels where i come from (the bahamas) they do not hire guys with locs in their hair .. when the guy asked the guest speaker why is it that locs that are kept clean is not acceptable .. she answered by saying that most people view those with locs as rastas and all the negative practices that a rasta is involved with (no offense to anyone) my point is when is is classified as discrimination?? if your rules and regulations handbooks assure you that you will be treated equally .. why is it that people make these exceptions? and if there are exceptions then why doesnt it list them. does this happen is the US too? Let me know what you think...