Front Suspension problems of the 2006 Suzuki Grand Vitara

I purchased my Suzuki Grand Vitara in 2006 brand new. Within 15k miles, the tires were worn out, so I took it in and they told me they would put 2 new tires on it, if I purchased and alignment, which I did. Now at 33k miles, my tires are worn out again and they said they had changed the specs on Suzuki's alignments, so now my alignment is out due to old specs. They did offer to put 2 new tires and align it if we purchased 2 more tires @ $380. 00. I told them I could get tires cheaper than that and they pulled the offer. No matter what happens, as long as the alignment is out, it will continue to eat my tires off. It is very unfair that I have to get an attorney to get Suzuki to fix my car that is under warranty. I know the tires are not under warranty, but the alignment is!!!.