Hi Kelly,
While there is not a standard option that exists to remove the "Price" column from the Registration Summary widget within the site designer, I have a workaround that you can try out. Within Marketing > Language Management, you can search for "Price" and find the text ID for EventWidgets_RegistrationSummary_PriceColumnName__resx and then you can paste a whitespace character in there and save it. Whitespace characters - you can copy the "zero-width space" character from this page and paste it in and save. You can also search for "Free" if you would also like to remove where it says "Free" next to the item(s) (if it is complimentary - the text ID for this one is EventWidgets_Products_Free__resx and paste that same whitespace character in there and save it.
See example screenshot below:

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Julia Plymack
Senior Client Success Manager
Cvent
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