There's probably a lot of reasons why people walk on the front of their feet or toes, but after searching online I didn't see anyone list the reason I do it. Maybe this help someone or researchers.

I only walk on the front part of my feet when around other people because it tends to make less noise. Making noise can draw more attention to you, and people might look at you. If you walk on the front part of your feet then your foot can act like a spring, a shock absorber. That's why they say to tippy toe if you want to be quiet.