Mads looks baffled hearing the outburst, initially decides to brush Lavender's words aside as an angry outburst but eventually decides to consider her.

"No, I won't" he responds calmly. "For one reason I just saved a few bucks from not taking the bus to get here. For another I saved time which I otherwise would have wasted by getting here. And even if none of those were the case I need to practice my precision and I can't do that without using my power. Where is this comming from?" he studies her face trying to figure out whether it's just frustration from being temporarily disabled or if there's something more.