Misleading box office statistics for "Grease"

At https://www.boxofficemojo.com/chart/never_in_top/?by_rank_threshold=1 there is a list of the Top-Grossing Movies That Never Hit #1.

At #32 on this list is Grease, for which Box Office Mojo has no weekend listed where it ranked higher than #2. 

However, for the film's original release in 1978, BOM has only one weekend's worth of results. As can be seen at https://www.boxofficemojo.com/weekend/by-year/1978/, BOM only has data for 16 of the 52 weekends of the year -- and for most of those weekends, only 1 or 2 films are listed. Other than Star Wars, most films have only one weekend's worth of data from 1978. This is a consequence of the undeveloped state of box office reporting in the 1970s.

While Grease apparently did not win its opening weekend against Jaws 2, BOM has no data at all for three of the next four weekends (and in the weekend for which it does have data, nothing is listed for Grease). Since Grease was the biggest box office hit of the summer of 1978 (see https://www.usatoday.com/picture-gallery/life/2019/06/22/biggest-summer-blockbuster-each-year-since-1975/39608665/ and https://www.boxofficemojo.com/season/summer/1978/) and in fact the entire year 1978 (see https://www.boxofficemojo.com/year/1978/), I suspect that it actually did win at least one of the weekends for which the data is missing.

Summary of the issue:

• Link to movie on IMDb: https://www.imdb.com/title/tt0077631/ 
• Link to movie on Box Office Mojo: https://www.boxofficemojo.com/release/rl2052556289/weekend/ 
• Grosses in USD: No correction needed, this is just a question of the film's ranking for weekends where the data is missing. I'm not disputing the total gross.
• Legitimate evidence of correct data: Not available to me.

My recommendation would be to just remove Grease from the list of the Top-Grossing Movies That Never Hit #1 because the data about what movies did hit #1 each weekend of its original release are largely unavailable.