Yes, by checking times between actions and number of actions in a time period, and blocking atypical activity. I was IP banned from a site once for a few months, after trying to scrape it too much and hitting links on the site that were hidden from humans.
The random wait settings specified in the post are better than nothing, but still too flimsy. You would need to put hours between requests, only request during a certain 15 hour periods, take days off, and eventually you aren't scraping regularly enough to do much good.
Scraping is not an API, and I should know- I used to do it for a living. Its unreliable. It requires constant maintenance. APIs can break too, but they are meant for the sort of consumption you are trying for.
If you scrape for a living, only do it as a side job.