What do you understand by tramps and their lifestyles? (chp18)
I am afraid I don't completely understand your question. I think you are just asking why the tramps live as they do and what role they play in the book. Is that right?
The reason the tramps are in the book is to help educate the prince. In his real life, he has had no experience of the lower classes of his kingdom. He has no way of experiencing first hand the effect that the king's (his father's) laws have on this type of person. It is largely the laws that have forced these people to live the way they do.
When the prince is taken captive by these people, he starts to learn more about his kingdom. Later on, this will have an impact on him and how he rules. That is the role of the tramps in this book.
In Mark Twain's book "The Prince and the Pauper" a young prince switches places with a street boy who bears an uncanny resemblance to the prince. The prince who had been subject to protocol and never had any freedom suddenly finds himself in a world very different from the one he had known. His initial experience was a guard treating him badly and throwing him out of the castle. Local boys set their dogs after him and beat him up. One of the means for gaining an income was to beg in the streets. The prince is expected to fill in for the pauper begging. The life style is rough and degrading. Although the prince had expected to have freedom to do what he wanted, he found out that a beggar's/tramps life was very rough.