Just… Don’t stop? Keep walking. They legally can’t stop you and they know it. It’s a psychological barrier, not a physical or legal barrier. Make direct eye contact, smile, say “No, thanks” and keep walking. It’s worked for me so far.
Please remember that your DM is a person. They are also playing the game and deserve to have fun, and for their boundaries to be respected. They are not just a physics engine for your shenanigans.
That being said, some DMs in specific groups might be totally fine with this. Just don’t spring it on someone without prior discussion and consent. That is (among other things) what session zero is for.
And if my grandmother had wheels she would be a bicycle!