For thousands of years people have met together in market places to buy and sell goods, food, trinkets, etc. But they also met to have conversations; to share news, gossip, or to hear and learn new ideas and thoughts.
Thomas records the sayings of Jesus. Don't think that Jesus just uttered these sayings out of the blue: they came during conversations.
Imagine Jesus walking into the market - the centre of village/town life - with his friends (some called disciples), men, women, and children. Perhaps he simply sat to watch the bustle and excitement then started to talk with his neighbour face to face. Passers-by may have overheard the conversation and gathered around to hear more from this travelling preacher. Others may have recognized him and joined the conversation rather than exchange news and gossip.
There are logia in 'Thomas' that record actual conversations, for example:
#6 "Do you wish that we should fast?"
#21 "Who do your disciples resemble?"
#60 "They saw a Samaritan, carrying a lamb"
#72 "Tell my brothers to divide my father's possessions with me"
In every case, Jesus answers questions with his unique message: the Kingdom is here and now, you too can find it so never cease from seeking.
Many of the most powerful conversations were with his special friends, his disciples. In logion #50 Jesus helps his friends with answers for their own conversations: "where were you from?" "who are you?" "what is the sign of your Father in you?" Words are poor in describing the indescribable, but Jesus leads them - and us - directly into the depths of spiritual discipleship with his answers.
Enter again the market place and seek out Jesus, have a conversation with him, ask your questions, then find your answers in the sayings recorded in the Gospel of Thomas. There is no better way nor place to find his treasures.