I have also been to foot washings and it is about people showing that they are not too good or better than the other human. We are all the same in Gods eyes. We baptize after someone has been saved and then hopefully they have fully surrendered to God and they are sanctified. Them the urge to sin is way lessened and they can focus on serving God and learning
Ephesians 6:13

Therefore put on the full armor of God, so that when the day of evil comes, you may be able to stand your ground, and after you have done everything, to stand.

Ephesians 5:25

Husbands, love your wives, just as Christ loved the church and gave himself up for her