I have had this discussion several times, and the answer is, yes, of course.

There are a lot of things that are codified in different theologies, and what a conflicting mess that is. Eat meat, don’t eat meat. Don’t eat pigs. Don’t jerk off. Don’t put milk in a refrigerator with meat. Don’t eat a sheep you’ve had sex with. Don’t mess up while you read this holy passage or you have to start all over again from the beginning. Don’t have blood transfusions. Don’t use gas engines or electric lights.

Those things exist outside secular morality. Secular morality is, in my perspective, always based on a kind of theft.
When you steal, of course, you deprive someone of that item. How about when you kill them? You deprive them of their life. How about when you rape them? You deprive them of their freedom to use their body as they see fit. I would define secular morality, again from my perspective, as the act of depriving someone or something of something to which it attaches value, described in it’s simplest form.

This discussion is as old as the hills and everyone disagrees, most often because they have an agenda. I don’t, I merely observe. A powerful lot of the non believers I know, and know quite a few, are well versed in this type of secular morality, and act it. This includes atheists, but rarely anti-theists. Anti theists all have an agenda, and it’s usually a religionof it’s own. That defines anti theism, actually. Plain old atheists, of which there are many, are usually just fine.

Anyway, I am of the opinion that you can be completely secular in your morals, and that’s fine with me- you might piss off someone because you like the occasional drink, or have a couple girlfriends instead of one, or like to sleep in on saturdays AND sundays and have bacon sandwiches at every meal, but that doesn’t make you a bad person, just because you don’t follow the tenets of a belief system you dont’ ascribe to.

When you do something, though, whether it be walking out of the restaurant knowing full well the cashier gave you change for a 50 instead of a 20, or whatever, be a man. Own it.