On-disk size of db increased after restore

I tried to restore one of our db backups to 3 different machines today.

After restore, all machines reported larger on-disk size, and also
psql's \l+ confirmed that.

Here is the live machine:
On-disk size: 84 GB
Size reported by psql: 79 GB

Backup machine 1:

On-disk size: 162 GB
Size reported by psql: 177 GB

Backup machine 2:
On-disk size: 179 GB
Size reported by psql: 177 GB

I have seen the opposite of this tons of times before, but I haven't
seen an increase after restore before. Does anyone know what may cause
this? Where should I look at?

Regards,
--
Devrim GÜNDÜZ
PostgreSQL Danışmanı/Consultant, Red Hat Certified Engineer
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