Absolutely! As I tell my colleagues all the time - the worst that'll happen is they say 'no'. I don't go in for full-blown haggling but I do at least ask for a discount. I'm also usually happy to walk away if they say 'no'.

Sometimes it changes their minds, sometimes it doesn't and I'll go back later and buy it anyway if I really want it. Same goes for hotels - if you book direct for the same price as a broker then they're not paying any commissions; you're happy, they're happy.