Other mistake: When Rodrick and Greg bought groceries, there was one bag of "Cheez Curlz" and it ended up in the hot tub at the motel. They weren't shown buying another bag yet they had one when the pigeons "attacked."
Other mistake: When the family got to the "Sleep Tite" motel, the "Beardo family" was in the hot tub. Greg apparently changed from his dark blue or black shorts to white and green swimming trunks when he went into the bathroom. A little later, he saw that the Beardos were returning to their motel room, meaning they were out of the hot tub. Greg already had his swimming trunks on when he asked if he could go to the hot tub. It didn't make sense for him to change as soon as he got to the motel.
Answer: "Beardo" looked intimidating and could easily frighten a child (or adult, for that matter). He also became enraged in front of children over scratches on his van - something minor that might bother an adult, but certainly not serious enough to produce Beardo's over-reaction. Greg did deny that he caused the damage. However, Beardo did not come across as being a rational adult or someone who a 12-year-old would feel comfortable standing up to or simply trying to reason with. Greg saw Beardo as a "difficult" and irrational person, so rightfully wanted to get away from him as soon as possible.
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