I'm not a Buddha expert but isn't this something he wouldn't have approved of?
Probably not. But it is also doubtful that he would have disapproved. It is easier to understand Buddhism if you look at the Buddha's teachings as guidance, good advice, and not as edicts. Also, honoring a teacher who has died in this way is a sign of respect and the trust you had in him/her not worship. He was the first and accordingly the highest teacher in this age so it does seem appropriate to me.
Properly absorbing all of his teachings would negate any tendency towards idol worship as well. There is a fine line of difference between honoring and worshipping but the meaning in that difference is profound.