Hello, Alexey,
This is expected as space will make every scrollable container including the page itself to scroll. This come directly from the browsers and the KendoReact Grid has no control over it.
In this case, I can suggest attaching an onkeydown event over the Grid DOM element or over the body and preventing it if it is space and also based on the target as otherwise, the user will not be able to type space inside text:
https://stackoverflow.com/questions/22559830/html-prevent-space-bar-from-scrolling-page
Regards,
Stefan
Progress Telerik