John Gill Commentary Mark 11:8

"And many spread their garments upon the way; and others branches, which they had cut from the fields." — Mark 11:8 (ASV)

And many spread their garments in the way
Instead of carpets to ride on, and in honour to him as a king:

and others cut down branches off the trees, and strawed them in the
way ;
in token of joy, as at the feast of tabernacles; (See Gill on Matthew 21:8).