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."
Continuity mistake: When Greg grabs the diaper, a kid with an orange T-shirt behind jumps inside the ball playground; but in the viral video he stays outside.
Continuity mistake: When Greg grabs the diaper in the ball playground, the position and number of all of the kids changes in every single shot.
Continuity mistake: When the Beardo's kids are pushing the cleaning cart at the motel, it hits his green VW van leaving a scratch / dent. In the wider shot, the cart has disappeared, even though it had practically stopped next to the van.
Revealing mistake: A "green screen" was obviously used at the restaurant (all-you-can-eat buffet). For example, the people supposedly seated in the booth behind Greg's mom were sometimes literally back-to-back with her - there was no back of the booth between them! They were also larger (closer).
Deliberate mistake: For an unknown amount of time during the family's four-day road trip, a Spanish tutorial cassette or CD was played. This would not be enough time for anyone to be able to fluently speak Spanish or carry on a conversation, but toddler Manny was able to do so near the end of the movie.
Visible crew/equipment: As all the stuff is flying out of the boat, you can see the hand of the guy throwing it out.
Continuity mistake: When the family's in the van driving to the hotel, Roderick and Greg switch seats although the van never stops.
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.
Factual error: The family's roadtrip was during "summer vacation", but there was intermittent Fall foliage (yellow, orange, red leaves) during their four days traveling. Quite often, the foliage was closer to what would be expected in late September or October and even November.
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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