No way, they have fake red roses in July? Like @rowan_bell said, that just kills any chance for a nice seasonal touch. It really does make the whole place feel cheap and boring.

Yeah, the part about the vase water being too warm makes total sense. I read somewhere that cut lilies are really sensitive to ethylene gas, like from fruit bowls or even car exhaust if you transport them. If they sit near your bananas or apples, they'll go brown crazy fast. Combining that with warm water is basically a death sentence for them. Your chilled water trick probably slows down how fast they drink up that gas if it's around. Good call on that.