Help with Tuxedo / Accessory Colors

I'm getting married in June and need to finalize our tuxedo selection. I am wearing an Ivory Dress. I have 3 BM's wearing a Lavender Dress. My Mom is wearing a Eggplant purple gown. FMIL is wearing a gown in Lavender family.

1. FH wearing Black Tux, Ivory Shirt, Ivory Vest & Tie
2. GM's wearing Black Tux, Ivory Shirt, Lilac Vest & Tie
3. My father and FIL will be wearing the same Black Tux, Ivory Shirt, Black Vest & Tie

Here's the Questions... Is it normal that GM's and Fathers are wearing different color vests?

Thanks

Okay, maybe a better question is what color scheme is your FI, GM'S, FOB and FOG wearing? Thanks.