Would you dare wash these feet?

There are alot of references to feet in the Bible. The washing of feet, Moses and then Joshua taking off their sandals while on Holy ground and thus revealing their feet (Ex.3:5, Josh.5:15), the angels around the throne of heaven having wings to cover their feet, feet being annointed (Lk.7:36-50), feet being kissed (Lk.7:38), golden rings worn on feet (Ex. 37:3), feet being cut off and hung up beside a pool (2 Sam.4:12), crippled feet (2 Sam.4:12), diseased feet (1 Kings 15:23), afflicted feet (Psalm 105:18), tinkling bangled feet (Is.3:16), naked feet (Is.20:2), licked dusty feet (Is.49:23), feet that run to evil (Is.59:7), feet sunk in mire (Jer.38:22), feet of iron and clay (Dan.2:34), nail-scarred feet (Lk.24:39), feet washed with hair (Jn.12:3), bound feet (Acts22:11), blood-shedding feet (Rom.3:15), feet like burnished bronze (Rev.1:15), feet like pillars of fire (Rev.10:1), even "beautiful" feet (Rom.10:15)... but I still cannot find the answer to the question, "Why did Moses have to take off his sandals and reveal his feet while standing on holy ground when the angels had to cover their feet with their wings when in the presence of our holy God sitting upon His throne in heaven?"
Anyone know?
OH! And really... would you dare wash these feet? If you think about it, these could be the beautiful feet spoken of in Romans 10:15... these could be the feet standing on a rock in Psalm 40...