The second histogram looks more human than the "not bot" first one?
Second user clearly takes a look before work, during their lunch-break and then after work?
There frequency of "game-changing" in comments would say otherwise. It's probably cron running at those intervals, not a work schedule.
There's also the point that one histogram is an order or two of magnitude larger than the other one. Larger samples of normally distributed data will tend to better resemble a normal distribution.