Well firstly I would not even use things like Machine learning without having in depth knowledge.

Simplistic things I would do if I had this time series is:

1) Write sql queries to understand which of the times you have the busiest , avg and low foot traffic.

2) Then try to visualize the whole time series , and you could use basic pattern matching algorithms to pick up patterns.

This two things will help you understand what your data set is telling you.

Then with that in hand you will probably in a better state to use machine learning algorithms.

Also , i am currently working in building something on time series and using time series analysis will help you much more than machine learning.

For example there are pattern recognition that you can use that uses every day data to show patterns and ones which use up as much as 3 - 6 months of data to catch a pattern.