Is there an error in the Script Editor's example scripts causing high CPU usage?

[VictoryStore]

I could be wrong, but I think there's an error in the example scripts for the Script Editor that's bloating CPU usage. The TieredPricingCampaign class has a section that reads:

applicable_items = cart.line_items.select { |line_item| product_selector.match?(line_item) }
next if applicable_items.nil?

However, when you print the applicable_items, a non-applicable line item prints an empty set instead of Nil. I swapped out nil? for empty? and it cut my CPU usage nearly in half.

Let me know if I'm missing something bigger picture about why it should be nil