There's an old joke that says if a man shows up with flowers, he's surely been up to no good. So we can't help but wonder what the Doors' Robby Krieger did to merit dropping $45,000 on a new ride for his better half.

The guitarist recently stopped by a Southern California Mercedes Benz dealership to make the purchase for his wife of 30 years, Lynn. But maybe he's been a good boy after all -- seems it was Lynn's birthday, and Robby was just gift-shopping.

He was reportedly considering the ML 350 SUV, but after a quick phone home, Lynn instead directed him toward the smaller GLK 350 -- and the lady's wish was his command. He promptly forked over 45 large for a tricked-out 2012 model in silver.

You know what they say -- "Happy wife, happy life" -- but guys, if it makes you feel any better, most ladies are perfectly content with a card and maybe a nice dinner out. Unless, of course, you've been naughty, in which case you'd better hope you have a bank account big enough to smooth things over.

If you're wondering what Robby's been up to when he isn't buying luxury rides, take a look at our review of the recently-released Doors documentary, ‘Mr. Mojo Risin’ – The Story of L.A. Woman.’