I was recently at the Sam Ash in NYC and I decided to play one of the 4 string Czech made Spectors. Pretty cool bass. I wanted to check out its slap tone, so I started to slap on it. I wasn't slapping hard, just a normal slap and one of the guys who worked there got pretty angry at me and said, " You can slap on this bass! It has nickel frets; if you slap on it, you'll ruin the frets." I thought this was kind of weird, I never heard that before. Is this true?...you're not supposed to slap on a bass that has nickel frets?