Hypothesis: There could be an adulterant in the darker gear that increases its ability to enter via the nasal mucous membrane. Where's Sprout when you need him for a quick biochemical question?Patronised, ex-bloody-xactly. Anyway, you gave him the tenner. It was his money, and his choice of what he was going to spend it on, not yours and not your girlfriend's either. If something comes with conditions, it's not really a gift -- it's a stick that you are using to beat them with to make them behave a certain way that you want. I'm not sure I would want to accept such a thing, and just hope I am never desperate enough not to be able to refuse it.
You know that famous psychology experiment where they offer a kid a sweetie and say You can take that sweetie now if you want it; but if you leave it alone for 5 minutes without touching it, you can have another sweetie as well ? Well, sometimes, just sometimes, one sweetie right now is a better deal than two sweeties, three hundred million of the longest, most agonising microseconds ever in the future. And you can probably never really totally understand that, unless you have ever actually experienced a real life one-sweetie-now situation yourself.