As others have said, this looks like a case of conflicting expectations from GM and Players.
As GM, you need to know if your players are on the same page as you for a hard-hitting, savage campaign.
Normally in Shadowrun, the answer is "Hell no" as the players are already scraping Cash and Karma to get by, and suddenly needing a new hand or 20 Karma to replace a point of burned Edge means that the last few missions have been for nothing.
If however, you tilt the balance to make recovering from these options a bit easier (upping Karma rewards, Cash, Contacts etc), then the Players may be more open to the odd lost attribute, appendage or Magic point.
By default though, SR4 is already very damned dangerous and if your PC's are playing it smart, then they both:
A) deserve to be rewarded for it
B) look like they've already chosen a limited danger level by default.
We had a PC in Ghost Cartel's adventure try Tempo a few times, as it looked like fun and he was in the nightclubbing scene via background. He developed a mild addiction to it very quickly, but then when further scenarios came about in the adventure, he started spending Edge on those Willpower rolls to go cold turkey. Sometimes just the threat of what could happen is enough to scare the PC's... don't need to permanently impair them...just give them some temporary 'issues'