Forcing multiple-unit pricing likely increases sales. You probably came to the purchase page just needing one. But you’re probably 𝖽̶𝖾̶𝗌̶𝗉̶𝖾̶𝗋̶𝖺̶𝗍̶𝖾̶ motivated enough to pay extra for a bundle of two if you have to! You’ll justify it by telling yourself “I might need the second one later”, but I’ll bet a lot of them end up going unused.

Raising the entry price slightly perhaps also makes people think a little harder about whether they really need to use a TSI or whether other support channels (Stack Overflow? Reddit?) might be more appropriate.